There is a lot of choices.
Make a list of your requirements first. It's good to think about the future. Top of my basic audio interface list is the Tascam us 2x2. At that price point it beats the competition with features and possibly the pre amps.
http://www.sweetwater.com/store/detail/US2X2?adpos=1t2&creative=163158737695&device=c&matchtype=b&network=g&gclid=CjwKEAiAyO_BBRDOgM-K8MGWpmYSJACePQ9CtoiIVnMYAiDihsRDtnIfhm0P6mBDfYGn8PNv_ksPlhoC3njw_wcB Here's my shopping list to ponder:
What kind of connectivity do you require? and how many of each.
These are some of the options:
XLR, 1/4", Combi jacks, RCA, ¼” line level, ¼” Instrument level ,MIDI, SPDIF, ADAT,MADI
How many ins and outs do you think you'll need now
and in the future?
Are they accessible? Front or rear
Are all ¼” jacks Balanced?
Is there a true stereo pair? Some don’t have a matched set of inputs.
Pre Amps will fall under the “you get what you pay for” rule, but check out the reviews anyhow.
A/D convertors will also fall under the same rule and generally all are good these days.
Are there peak level meters or just a little LED for each input?
Are there channel Insert jacks?
Are there separate controls for Monitor level and headphone level?
Is there a blend control for mixing Source with Computer ( DAW) ?
How many Headphone jacks? A level for each?
Are the input pads or line / Instrument toggle switches on the front, back or software controlled?
Is it a metal box or cheap plastic? Is it light and portable or large and bulky, Rack mountable?
Does it have an on / off switch?
Does it use Buss power or a power supply? Buss power can have issues with noise and Phantom power. Look for at least an optional power supply.
Does it have DSP effects built in?
Does it use a GUI mixer? Having a software (GUI) mixer adds more options.
Can it be used as stand alone? Some interfaces are also handy as a small mixer.
What are the Round Trip Latency (RTL) specs? Do you need low RTL for real time processing?
Low RTL is going to be at a higher price point. A $200 interface will have hidden buffers etc.
Zero Latency monitoring is not the same as RTL. All interfaces have some latency.
Zero latency is just marketing hype for monitoring directly from the interface.
And most important of all, Does it have top notch drivers for your OS.
What is the word on support from the company?
Does it come with free software, An LE version of a DAW you would like to try?
Everyone will recommend the interface they have chosen, that doesn't mean it is the right one for you.